Hot-air furnace



.I. P. JOHNSON.

HOT AIR FURNACE.

APPLICATION Fl-LED DEC.2.19I8.

1 ,3 1 7,794. Patented OH. 7, 1919.

m 4 I 1 a a THE COLUMBIA PLANOGRAPH cm, 'Asuma'nw n k timafnn s ra'rns FATEhTT carton.

JAMES P. Johnson, on nnsr CLEVELAND, onio.

HOT-AIR FURNACE.

Application filed December 2, 1918. Serial No. 264,945.

manufactured gas is used as a heating me-.

dium.

The primary object of the present invention is to provide means for economizing in fuel, or increasing the heat efiiciency of the furnace.

A further object of the invention is the provision of simple and effective means for the purpose above set forth, that can readily be installed in gas furnaces of thecommon universal construction, without any change or alteration in the arrangement or construction of the parts that are already embodied in the furnace structure.

As the improvement is only applicable where gas is employed, a further object is to provide means for effectively carrying out the purpose set forth, and that can readily be removed from the furnace'when it'is de sired to use coal as the heating medium.

With these objects in view the invention consists in the novel .construction and an rangement of the parts of an auxiliary element and its cooperative combination with other elements of the furnace, as set forth.

in the following description and definitely pointed out in the appended claims, reference being had to the accompanying drawings which are made a part of the specification and in which similar characters of reference are employed to designate corresponding parts.

In the said drawings Figure 1 is an elevation of a hot-air furnace embodying the invention, partially in central vertical sec tion. Fig. 2 is a section on line 22, Fig. 1. Fig. 8 is a fragmentary plan view of the auniliary member, on an enlarged scale, and Fig. 4 illustrates a fragment in perspective illustrating a different connecting means that will hereinafter be described. W

Referring now to the drawings. Figs. 1

and, 2 illustrate substantialv a lencwn Spiecificationof Letters Patent.

Patented'flct. 7, 1919.

construction'of hot-air furnaces in common domestic use, with the improvement associated therewith. v

. The casing 1 incloses a fire-pot 2 provided with a dome 3 and 'a grate 4. Connections 5: are providedfor conducting'fuel gas from the source of supply, through. mixers 6 to thefirc-pot 2. The connections 5 communicate with a conduit 7 located in the wall of the fire-pot and provided with a plurality of apertures or jets 8 that open into the combustion chamber 9. When gas is used as a heating medium-the fuel is ignited at the jets 8, thereby heating the fire-pot 2 and dome 3, andv imparting heat to the surrounding confined air. hen coal is employed, the gas supply is cut off and'the coal is placed in the fire-pot on top of the grate 4. The heat generated by the burning of the coal produces the same result as that set forth in connection with'gas burners.

The'above brief description is applicable to the operation of hot-air furnaces heretofore in common use and therefore the construction so far described is old in the art.

As hereinbeforestated, the present invention provides for increasin the efliciencv ofthe furnace and is applicable to hot-air furnace construction'in general, as will readily be seen from the following description of the improvement and its association with the other elementsof the furnace structure.

In the embodiment as illustrated, a cylindrical drum or shell 10, preferably made of sheetmetal, provides a support for an exterior covering of sheet asbestos 11, which is riveted thereto. The covering provides a base for attachment by suitable adhesive, such as asbestos glue, of a layer of fibrous, fluffy or soft loose asbestos 12.

The diameter of the combined member. 10, 11 and 12 is somewhat less than the in terior diameter of the fire-pot 2, as best shown in Fig. 1, and for convenience of installation the shell 10 with its attached ele ments is made in segmental sections, means being provided for connecting the several segments to form the complete cylindrical shell. As shown in Figs. 1, 2 and 3, the segmental members 10 are provided with inturned registering ears 10 which are connected by bolts 10 By making the improved device in sections it can easily be of an assembled Within the fire-pot, and as readily 81TiOV6Cl when: it is desired to use coal for ue a Fig. 4: illustrates a different connecting means, Wherein a clip 10 is pivoted to an ear 10 of one segment, and is adapted to engage an car 10 provided on an adjacent segment. T i

The improvement, fabricated as above described, is installed in the furnace, resting on the grate 4, Within and concentric to the fire-pot 2, the fluffy fibrous layer12 facing the inner Wall of said fire-pot. The ignited gas through the jets 8 penetrates the fibrous non-inflammable material 12. Owing to the fluffy fibrous consistency of member 12 it is proved device.

quickly heated or brought to a glowing cond1t1on,'Wh1ch enhances the combustion, in-

-tensifies the heat and increases the radiation, thereby producmg a greater amount of heat in proportion to the fuel consumed. The gloWof themember 12 provides for the combustion, or maintenance of ignition :stalled in a domestic hot-air coal furnace,

that a given required amount of heat can be obtained at a saving of more than one-half of the fuel consumed, when compared With a similar furnace not equipped With the im- 7 While I have shown and described a simple practical "construction of the improvement, it Will be understood that there may be changes'and alterations in the details of construction and in the material specified, Without departing from the nature Copies ot'this patent may be obtained for and extending, vertically therein, and a coating ofnon-inflammable loose fibrous material attachedto the exterior of the cylindrical shell.

2. In a hot-air furnace, a fire-pot provided with gas jets on the interior thereof, a cylindrical shell adapted to the interior of the fire-pot,-spaced from the Wall of said firepotandextending vertically therein, said shell being in segmental sections having a non-inflammable fluify fibrous covering on the exterior thereof, and means for connecting the several segmental sections.

3. In a hot-air furnace, the combination of a fire-pot provided With gas jets on the interior thereof; a shell Within said fire-pot,

spaced from the Wall thereof, and extending vertically therein; and a non-inflammable 'flufi'y fibrous coating attached to the exterior of said shell. J V I 4:. In a hot-air-furnace, a fire-pot pro vided With gas'jets on the interior thereof,-

a metal cylindrical shell adapted to the in terior of the firepot,' spaced from the Wall of said fire-pot and extending vertically therein, said' shell comprising a series of segmental sections having a coating of asbestos glue attached to the exterior thereof and a coating of loose fibrous non-inflammable material attached to the exterior of the first coating, an'd'means for connecting the several'segm'ental sections.

In testimony whereof I aflix my signature.

I JAMES P, JOHNSON.

five cents eac11, by addressing the Commissioner of Patents, Washingt9n,D; q. 7 f 

